It’s a tough life out there for crafty 33-year-old right-handers who barely scrape 90 mph. A life where frequent adjustments aren’t just important, but paramount if you want to keep your job. Where the ceiling is middling fifth starter and the floor is rookie realtor. Where the margin for error is razor thin, and the difference between success and failure could depend on how you sleep. Where even the Orioles (the Orioles!) could release you from their barren pitching staff when things go awry.

Gonzalez has been walking the backend-starter tightrope for years now, finding success at times but quickly slipping into troubled waters following the regression monster’s arrival. The veteran has a 3.88 career ERA, but anemic strikeout rates have kept him from being more than a no. 5 starter, eclipsing 1.0 WARP in a season just once in six years. Gonzalez has long known how easy it is to lose your way in the big leagues—in 2014, despite squeaking across a 3.23 ERA over 159 innings, he was released just a season later—but this season has been another major test in his ability to adapt.

While the starter found his groove to kick off 2017 by stringing together a pair of eight-plus-inning, one-run performances, the long starts seemed to take their toll and his velocity waned. Sure, it was just a couple ticks on the radar gun, a change which would have little effect for high-octane arms, but the slip was season-altering for Gonzalez. It quickly became apparent that Gonzalez couldn’t make it work with a 90-mph heater, although the righty continued plodding along for another couple months. He eventually landed on the disabled list with a 5.15 ERA and a diagnosis of shoulder inflammation.

A month later, Gonzalez was activated from the DL and matched Clayton Kershaw pitch-for-pitch in a 1-0 loss, showing renewed velocity and a revamped game plan. His next start out: more of the same in a one-run, seven-plus-inning performance against the Cubs. Although he ran into trouble by allowing seven runs over 1 2/3 innings against the Red Sox two outings later, Gonzalez quickly bounced back and stopped the powerful Astros in their tracks. Seven-run outing and all, Gonzalez has managed a 3.11 ERA since being activated from the disabled list and has been Chicago’s best starter in the dog days of the summer.

As encouraging as the turnaround is, Rangers fans should temper their expectations. The long-term upside for Gonzalez is low, and so is the floor. Things can change in an instant for players like him, both for the good and the bad, as we’ve seen in his two-act season. Perhaps Gonzalez can keep it going—that revamped game plan is headlined by a much-improved sinker, one that he’s now using as often as the four-seamer but with more ground balls and less hard contact—and there’s more to him than that 4.31 ERA suggests. Then again, he could very easily give up seven runs in his next start, as he’s so prone to doing. Regardless, he compares favorably to the cacophony of arms in the back of the Rangers’ rotation.

One of the most common ways to frame acquisitions is as either a buy-low or sell-high move—capitalizing on a transient player stock to maximize the value received in the deal. If we want to move to the extreme "buying low" side of the spectrum, we might see the following deal: the Cubs finding a previously good player in Martin who has since bottomed out in value.

In fairness, that may obscure the main goal of this deal for Chicago—they aren’t trading for Martin expecting him to reincarnate into the everyday center fielder of yesteryear. World Series hangover and all, this is still the Cubs, a club as deep as they come all around the field, outfield being no exception. Martin slots in behind three very solid center fielders on the depth chart in Albert Almora Jr., Ian Happ (who also plays at second base), and Jon Jay, a trio of guys all likely able to find everyday jobs on other teams.

Martin, on the other hand, is fresh off a three-month exile to Triple-A following a brutal start to the season with the Mariners, one which featured a .111 batting average over 58 plate appearances. He hit exactly as well as you’d except a former 4.0-WARP player would in the minor leagues, and was subsequently brought back up to Seattle with mild success. Well, it isn’t tough to improve upon a -18 wRC+, but his .230/.266/.426 line might play in the big leagues as a fourth or fifth outfielder.

So, of course, a fifth outfielder is exactly what the Cubs are hoping to find in Martin. Another team might take a gamble on him hoping he may recapture his 2016 form—15 home runs and 24 stolen bases with plus defense—but the Cubs will look for some late-game defensive relief and pinch-running duties. Anything on top of that is gravy, though Martin still has some pop in his bat and can fly around the bases. Maybe he can find his swing again, make a small sacrifice to the baseball gods in hopes of improving that .205 BABIP, and become a solid player again (it wouldn’t be the first time), but realistically he probably won’t get the opportunity to do that with the Cubs. Maybe next year in a new gig, but his role will be limited in Chicago.